lix/src/libexpr/fetchurl.nix
2022-09-16 01:54:24 -07:00

44 lines
1.3 KiB
Nix

{ system ? "" # obsolete
, url
, hash ? "" # an SRI hash
# Legacy hash specification
, md5 ? "", sha1 ? "", sha256 ? "", sha512 ? ""
, outputHash ?
if hash != "" then hash else if sha512 != "" then sha512 else if sha1 != "" then sha1 else if md5 != "" then md5 else sha256
, outputHashAlgo ?
if hash != "" then "" else if sha512 != "" then "sha512" else if sha1 != "" then "sha1" else if md5 != "" then "md5" else "sha256"
, executable ? false
, unpack ? false
, name ? baseNameOf (toString url)
, impure ? false
}:
derivation ({
builder = "builtin:fetchurl";
# New-style output content requirements.
outputHashMode = if unpack || executable then "recursive" else "flat";
inherit name url executable unpack;
system = "builtin";
# No need to double the amount of network traffic
preferLocalBuild = true;
impureEnvVars = [
# We borrow these environment variables from the caller to allow
# easy proxy configuration. This is impure, but a fixed-output
# derivation like fetchurl is allowed to do so since its result is
# by definition pure.
"http_proxy" "https_proxy" "ftp_proxy" "all_proxy" "no_proxy"
];
# To make "nix-prefetch-url" work.
urls = [ url ];
} // (if impure
then { __impure = true; }
else { inherit outputHashAlgo outputHash; }))